The invention is based on a wiper blade.
In windshield wiper systems for motor vehicles, a fastening part is generally secured to a drive shaft, and a pivoting part is connected to it via a shaft. The pivoting part is adjoined by a wiper rod, from which a wiper blade is suspended. The wiper blade has a support bracket system with a plurality of members and with intermediate brackets pivotably connected to a main bracket; claw brackets are pivotably connected to the ends of the intermediate brackets and have retaining claws on their ends. A wiper strip is retained by the retaining claws. The support bracket system makes it possible for the wiper strip to adapt to a curved window during wiping. A spring rail is placed in the rubber profile of the wiper strip in order to achieve a uniform contact pressure with the window.
When the windshield wiper system is actuated, the wiper strip slides over the motor vehicle window and in the process is subjected to unavoidable wear, which impairs the cleaning quality. The wiper strip must therefore be replaced from time to time. Since as a rule the support bracket system of the wiper blade is still fully functional by then, the end user is sold a so-called refill kit, so the old support bracket system can continue to be used.
From German Patent Disclosure DE 195 22 273 A1, a wiper blade is known into which a refill kit comprising a wiper strip with a spring rail and a securing body can be introduced. The spring rail is disposed in a head strip of the wiper strip, in a longitudinal channel that is closed all the way around and opens out at the end faces of the wiper strip. The securing body is slipped onto one end of the head strip and in the process, with legs encompassing the head strip, engages longitudinal grooves on two opposed longitudinal sides of the head strip. It is thus fixed on the head strip except for the longitudinal direction.
The securing body has a fastening clamp, which presses channel walls of the head strip into recesses of the spring rail and thereby fixes the securing body, spring rail and wiper strip longitudinally relative to one another. Once the used wiper strip is removed from the wiper blade, the preassembled refill kit can be thrust into the retaining claws of the support bracket system of the wiper blade; the retaining claws engage the longitudinal grooves in the wiper strip. The securing body has not only the fastening clamp but a spring clamp with deflectable spring arms and hooks disposed on them. Once the refill has been thrust virtually all the way into the retaining claws, the hooks of the spring clamps are swiveled out of a retaining claw disposed on the outer end of the support bracket system, and on the other side they snap in the form of a snap closure onto the retaining claw, so that the securing body contacts the retaining claw on both sides and fixes the wiper strip longitudinally to the support bracket system.
The spring clamp is cut out of a larger sheet-metal part after a stamping or other cutting operation, either after or before a bending operation. The hooks are formed by a right-angle shoulder made in the cut outer contour of the sheet-metal part; after the bending operation, in the installed state, this shoulder extends in the direction pointing away from the window.
The thinner the metal sheet, the sharper are the edges that are created at the cut outer contour; they can be removed only with great effort and often not completely. When the refill kit is removed, with the spring clamp described, pressure must be exerted on the cut outer contour in the region of the hooks in order to unsnap it. The sharp outer contours can cause injury then. The risk of injury is present not only during disassembly but also during installation, cleaning, and so forth.